Ice making



July 24, 1962 D. E. M LEOD 3,045,445

ICE MAKING Filed Dec. 19, 1960 2 Sheets-Sheet 1 INVENTOR. DAVID a. MACLEOD ATTORNEY.

July 24, 1962 D. E. MaOLEOD 3,045,445

ICE MAKING Filed D60. 19, 1960 2 Sheets-Sheet 2 INVENTOR.

ATTORNEY.

Unitcd States Patent 3,045,445 Patented July 24, 1962 3,045,445 ICEMAKING David E. MacLeod, Syracuse, N.Y., assignor to CarrierCorporation, Syracuse, N .Y., a corporation of Delaware Filed Dec. 19,1960, Ser. No. 76,950

5 Claims. (Cl. 62-137) when a predetermined quantity of ice is availablefor use in the storage bunker. Though the control means contemplated bythis invention may be used in different forms of ice making apparatus,it is particularly suited for use in automatic ice making equipmenthaving an ice forming compartment and a storage compartment incommunication therewith. Within the ice forming compartment are aplurality of tubular members, openat both ends. The tubular members areprovided with refrigerated inner surfaces over which water iscontinuously circulated.

During operation of the ice making apparatus, portions of the circulatedwater are formed into ice, and subsequentlyharvested. The harvested icepasses by gravity into a storage compartment and remains there untilremoved by the consumer.

As is apparent, the quantity of ice which can be received in the storagecontainer is limited by the capacity of the container, hence it isnecessary to provide control means for effecting cessation of deliveryof ice from the ice forming compartment. Heretofore, it has beensuggested that a thermostatic sensing element capable of actuating aswitch in the circuit of the compressor motor of the refrigerationsystem be employed.

Once the ice in the storage compartment builds up to the extent thatportions thereof engage the thermostatic sensing element and so lowerits temperature, a switch is opened to deenergize the compressor motorand terminate operation of the ice making apparatus.

The use of a thermostatic sensing element has sometimes proveninadequate in that the sensing element must be set extremely close to afreezing temperature and is subject to premature tripping by cold watersplash, cold air drafts, or inadvertent ice pile up'b y the operatorduring ice removal. Additionally, barometric conditions result in avariation in effectiveness of the thermostatic element. The delicatenature of the capillary tube conventionally employed also presentsproblems.

7 It is with these problems and desiderata in mind that the present icemaking apparatus having improved control means for limiting the level ofice accumulations in the ice storage bunker of the ice making apparatushas been evolved. The icemaking apparatus is provided with controlmeansresponsive primarily to the presence of ice accumulations and notsubject to being activated by extraneous influences such as watersplash, temperature and humidity conditions, or ice removal or deposit.

. It is accordingly a primary object of this invention to provide an icemaking apparatus having an improved con trol for limiting iceaccumulations in the ice storage coni Y tainer in such apparatus.

Another object of the invention is to provide ice making apparatus withcontrol means for limiting ice accumulations, with the control means notsubject to barometric conditions A further object of the invention is toprovide ice making apparatus having control means for limiting ice ac- 0the storage bin.

cumulations with the control means not subject to premature actuation bycold water splash, ice removal, or the like.

An additional object of the invention is to provide ice making apparatushaving ice sensing control means which respond relatively fast toaccumulations of given ice quantities.

It is an additional object of this invention to provide an ice makingapparatus with an ice sensing control for limiting ice accumulations inthe ice storage container,

with the control being relatively simple in production,

economical in manufacture and maintenance, and relatively foolproof inoperation.

These and other objects of the invention which will become hereafterapparent are attained by provision in an ice making apparatus of acontrol arranged in the ice storage container in which ice is retaineduntil consumed, the novel control terminatingoperation of the ice makingapparatus when a predetermined quantity of ice is deposited in thestorage container. The novel control means acting to determine and limitthe quantity of ice received by said storage means comprise energysensitive means, such as a photo-electric cell, positioned in thestorage means with said energy sensitive means arranged to receiveenergy such "as light from energy emitting means, such as a lightsource, directing a beam above the point of maximum desired iceaccumulation in the storage means. The photo-electric cell is seriescoupled to a normally closed relay which may be encased therewith in acommon housing. A time delay relay, with normally open contacts, apull-type reset solenoid, and a normally closed momentary contact typeswitch are arranged across the line to which the photo-electric cell andnormally closed relay are connected. In use, the aforedescribedcomponents are arranged to control the energization of the ice makingapparatus, so that the detection of a given quantity of ice in the icestorage bin or bunker results in termination of operation of the icemaking apparatus. A sustained interruption of the light beam emanatingfrom the light source deenergizes the relay in series with the lightcell closing its contacts Thereupon, the solenoid is energized to openthe contacts of the momentary contact switch, thus breaking the circuitto the compressor in the refrigeration system.

A primary feature of the invention resides in the fact that the timedelay relay prevents termination of the ice supply byextraneous lightbeam interruption such as might be caused by water splash from the iceforming means into the ice storage bunker or by the action of anoperator in removing ice from the storage bunker. Only upon theoccurrence of a sustained light beam interruption, such as would occurupon the accumulation of a given quantity of ice, is the control circuitactivated to render the refrigeration system inoperative.

The specific details of a preferred embodiment of the invention andtheir mode of functioning will be made most manifest and particularlypointed out in clear, concise and exact terms in conjunction with theaccompanying drawings, wherein:

FIGURE 1 is a diagrammatic view of the ice making apparatus of thepresent invention including a portion of the control system thereof;

I FIGURE 2 is a schematic wiring diagram showing a preferred circuitarrangement of the components of the novel control system with less thana predetermined quan-' tity of ice in the storage bin; and

FIGURE 3 is a schematic wiring diagram showing a preferred circuitarrangement of the components of the control system with a predeterminedquantity of ice in Referring more particularly to the drawings, there isshown in FIGURE 1 an arrangement embodying my into the evaporator coil.Other expansion means may be provided, if desired. At the other end ofthe evaporator coil, there isa suction line 9 which conducts the gaseousrefrigerant to the compressor 4. Accumulator 10, in line 9, acts as areservoir for unevapora-ted liquid refrigerant en route to thecompressor.

The condenser may be of the air-cooled or of the liquid-cooled type, asdesired.

The means for supplying water to be frozen includes tank or reservoir 11and pump 12 for feeding water from the tank through line 13 to header 14disposed above the ice forming members 2. The header has a plurality ofopenings therein permitting the water to enter the ice forming members 2via dispersion plates 15. A deflection grid or screen 23 is locatedbeneath the ice forming members at an angle thereto so as to permitwater to pass by gravity into tank 11 while guiding the ice to storagebunker or bin 17.

In order to maintain a predetermined amount of water in the supply tank11 when the ice making apparatus is in operation, a float-controlledvalve 18 is shown connected to a supply line 19.

During the freezing cycle water is circulated from the tank into therefrigerated ice forming members 2, where part of the water is formedinto ice and the remainder is returned to the tank by gravity. The waterreturning to the tank has been reduced in temperature by passing throughthe refrigerated ice making members. Inasmuch as pure water is frozeninitially, the water returning to the tank has a substantially highmineral content and suitable means (not shown) may be provided forremovingthis water periodically from the tank.

After the ice has been formed completely in the ice forming members 2,the water which is being introduced from the header into the ice formingmembers is caused to overflow due to the presence of the ice whichrestricts further passage of the water to actuate a control arrangement(not shown). The particular control means preferably employed is shownin Patent No. 2,755,098, granted December 25, 1956. The control meansenergizes a solenoid 21, which. in turn opens bypass valve 22 in thebypass line 20. The bypass line is connected between the discharge line6 of compressor 4 and the evaporator coil feed line 7. When bypass valve22 opens, relatively hot gaseous refrigerant flows directly to theevaporator coil from the compressor 4 so as to cause a thawing action inthe ice making members 2, which removes the ice therefrom.

Referring now more particularly to FIGURES 2 and 3, the control system25 determining the quantity of ice received in storage bunker 17 is seento comprise a light source 26 arranged on one side of the bunker or bin17. This'light source 26 is of a conventional type and is hereschematically shown as an incandescent lamp, but it will be understoodby those skilled in the art that any form of light source may beutilized. It will also be appreciated that any emitter of energy may besubstituted within the scope of the invention.

Energy'sens'itive means here shown as light sensitive means in the formof photoelectric cell 27 are arranged on a'wall of storage bunker 17opposite'to that of the radiant energy source in a position such thatthe energy beam emitted will pass in'a path above the point of maximumdesired ice accumulation. Photo-electric cell 27 is arranged inseries'withrelay'ZS having normally closed contacts, and the seriescoupled relay 28 andcell 27 are placed across the power'supply lines Land L Time delay relay 29 is coupled to relay 28 so that upondeenergization of relay 28 its contacts will assume their 4 normallyclosed position permitting current to flow to relay 29, which after apreselected time interval will have its normally open contactsclosed.

A pull-type reset solenoid 30 is coupled for energization by the closingof the time delay relay contacts, and armature 31 of the solenoid iscoupled to the arm of momentary contact switch 32. Switch 32 is arrangedin the power supply circuit of the mechanism supplying ice to thestorage bunker, which in this instance is shown schematically ascompressor motor 33 in the refrigeration circuit of the ice makingapparatus.

During the operation of the automatic ice making apparatu's, quantitiesof ice are alternately formed and harvested in the manner described-above.' It will be obvious that a substantial amount of ice will becollected in bunker 17 The control for limiting ice accumulations in theice storage bunker is arranged in combination with the ice storagebunker" or bin 17 so that the energy emitted in the form of a light beamfrom the energy emitting means here'shown ascomprising light source 26will be passed over the point of maximum desired accumulation of ice inthe bin 17.' Energy sensitive means in the form of photo-electric cell27 are arranged to be impinged on by the energy emitted by the lightsource 26, thereby permitting current to flow through relay 28 with theresult that the relay contacts remain open. With the contacts of relay28 open, time delay relay 29 and solenoid 30 are not energized' so longas light falls on the photo-electric cell 27. Switch 32 under theseconditions remains closed and the compressor 'motor 33 remains energizedto continue the production of ice. Upon the accumulation of ice in bin17 to a point where there will be sustained interruption of the lightbeam, photo-electric cell 27 interrupts the fiow of current'throughrelay 28, thereby permitting the relay contacts'to assume their normallyclosed position. If these normally closed contacts remain closed for aperiod sufficient to permit time delay relay 29 to actuate solenoid 30,thearmature 31 of solenoid 30 which is coupled to momentary contactswitch 32, permits the opening of switch 32 breaking the circuit tocompressor motor 33' and discontinuing the production and delivery ofice.

It will be observed that periodic interruption of the energy beam suchas might occur due to momentary build-ups of ice in the bin duringdeposit or removal of the ice, or interruptions due to water splash, donot result in 'a cessation of delivery of ice to the bunker, since thetime delay does not permit actuation of solenoid 30.

It will further be apparent that though switch 32 has been described asconnected to control the operation of compressor motor 33, that theswitch 28 may be arranged to interrupt current flow to either icedelivery apparatus or ice forming apparatus.

It is thus seen that an ice making apparatus has been provided withsimple, effective means for limiting ice accumulations in the storagebin or bunker thereof. Extraneous factors such as cold water splash,cold air drafts, or barometric variations, which sometimes adverselyaffected the operation of previous ice making apparatus, do notinfluence the operation of the present ice making apparatus.

The above disclosure has been given by way of illustration andelucidation, and not by way of limitation, and it is desired to protectall embodiments of the herein disclosed inventive concept within thescope of the appended claims.

I claim:

1. In an ice making apparatus, the combination of means for forming ice,means for harvesting the formed ice, a storage bin placed below the iceforming means for collecting the harvested ice, and means responsive tothe collection of a predetermined supply of ice in the storage bin fordiscontinuing operation of the apparatus, said discontinuing meanscomprising energy emitting'means arranged in the storage bin to pass abeam of energy in a path above the pointof maximum desired iceaccumulation in said storage bin, energy sensitive means arranged in thestorage bin, and time delay meanscoupled to said energy sensitive meansto delay the response thereof to the interruption of the energy beamemitted by said energy emitting means, whereby upon interruption of theenergy beam emitted by said energy emitting means by the harvested ice,said energy sensitive means will be actuated to discontinue operation ofthe apparatus.

2. In an ice making apparatus, the combination of ice forming means,means for supplying water to be frozen to said ice forming means, meansfor freezing a portion of the Water and for harvesting the formed ice,an ice storage bunker for collecting the ice, and control meansincluding an ice level control for limiting the level of accumulation ofice in said ice storage bunker, said control means comprising a circuitcoupled to a source of electrical power, said ice level controlcomprising energy emitting means arranged on one side of the storagebunker to emit an energy beam in a path across the area in which ice isaccumulated in the storage bunker, the path lying at a level immediatelyabove the point of maximum desired ice accumulation, energy sensitivemeans arranged on a side of thestorage bunker opposite to the side onwhich said energy emitting means are arranged, switch means in saidcircuit actuated by said energy sensitive means to deactivate the icemaking apparatus upon the interruption of the energy beam by anaccumulation of ice in the storage bunker above a desired level, andtime delay means coupled to said energy sensitive means to delay theactuation of said switch means, whereby momentary interruptions of theenergy beam by watersplash or the like will not deactivate the icemaking apparatus.

3. A method for operating an ice making aparatus comprising forming andharvesting ice, collecting harvested 1'ce in a storage bunker, emittingan energy beam from one side of the bunker along a path across the areain which the ice is accumulated in the bunker, the path lyingimmediately above the point of maximum desired ice accumulation, sensingthe energy beam at the side of the bunker opposite to the side fromwhich it was emitted and switching off the flow of power to the icemaking apparatus upon the interruption of the energy beam by anaccumulation of ice in the storage bunker above a desired level, theswitching oil of the flow of power being delayed for a fixed timeinterval after interruption of the energy beam whereby momentaryinterruptions of the energy beam by water splash or the like will notdeactivate the ice making apparatus.

4. In an ice making apparatus, the combination of means for forming ice,means for harvesting the formed ice, a storage bunker for receiving theharvested ice and ice level control means for limiting the level ofaccumulation of ice in the ice storage bunker, said control meanscomprising energy emitting means arranged on one side of the storagebunker to emit an energy beam in a path across the area in which ice isaccumulated in the bunker, the path lying at a level immediately abovethe point of maximum desired ice accumulation, energy sensitive meansare arranged on a side of the storage bunker opposite to the side onwhich said energy emitting means are arranged, relay means coupled tosaid energy sensitive means for actuation thereby, time delay meansbetween said energy sensitive means and said relay means to delay theactuation'of said relay means by said energy sensitive means, and switchmeans activated by said relay means controlling the powering of the icemaking apparatus.

5. In ice making apparatus, the combination of ice forming members,means for supplying water to said ice forming members, means for formingice on the forming members and for harvesting formed ice from theforming members, an ice storage bin for collecting formed ice, and acontrol for limiting the ice accumulations in the bin, said controlcomprising a photoelectric cell mounted on a wall of the bin, a lightsource directing a ray of light against said photo-electric cell along apath immediately above the maximum height of desired ice accumulation, acircuit coupling said photo-electric cell to the forming and harvestingmeans, said circuit being actuated when said photo-electric cell isimpinged on by the light beam from said light source to permit operationof the forming and harvesting means, and being actuated to discontinueoperation of the forming and havesting means upon interruption of thelight beam, said circuit comprising a relay with normally closedcontacts which are maintained open when the photo-electric cell isimpinged on by the light beam; a time delay to delay the passage ofcurrentthrough a circuit comprising the normally closed contacts; asolenoid in the circuit controlled by the time delay relay; and anormally closed switch controlling the actuation of the means forforming and harvesting ice, said switch coupled to said solenoid formovement between a forming and harvesting means actuating position anddeactuating position.

References Cited in the file of this patent UNITED STATES PATENTS2,374,846 Thresh May 1, 1945 I 2,865,262 Fradenburgh Dec. 23, 19582,895,489 Foust July 21, 1959 2,964,359 Abonnenc Dec. 13, 1960 2,970,453Harle Feb. 7, 1961 relay coupled to said relay UNITED STATES PATENTOFFICE CERTIFICATE OF CORRECTION Patent No. 3 O45 n445 July 24 1962David'E. MacLeod It is hereby certified that error appears in the abovenumbered patent req'liring correction and that the said Letters Patentshould read as corrected below.

Column 1 v lines 10 and 11 for "predetermine" read predetermined column6 line 7, strike out "are".

Signed and sealed this 4th day of December 1962.

(SEAL) Attest:

ERNEST W SW1 D DAVID L. LADD Attesting Officer Commissioner of Patents

